Statistical analysis was performed The

Statistical analysis was performed. The age distribution of the study population, duration of surgery, the surgeon’s grading of comfort, the patients’ grading of comfort and total sedation dosage were analysed with Student’s “t” test; the sex distribution by the “Z” test, and the requirement of incremental sedation and incidence of vitreous prolapse by the Chi Square test. All statistical calculations were performed with Microsoft Excel (Microsoft Corp., Redmond, WA, USA). P values for “Z” test and Chi Square tests were calculated with an online web based calculator. P<0.05 was considered statistically significant.
Results
Age and sex distribution were similar between groups. The average duration of surgery was 7.42% longer in Group P (51.71min) compared to Group T (47.87min). This difference was not statistically significant (P=0.06275). The average patient comfort level in Group P was 5.67% greater than Group T. This difference was not statistically significant (P>0.05). The average surgeon comfort between groups was similar (P>0.05). Incremental sedation was required in 16% of patients in Group T compared to 8% in Group P. There was no statistical difference in incremental sedation between groups (P=0.218363). The total sedation dosage required for each group was similar. The incidence of vitreous prolapse was statistically significantly higher by 14% in Group P compared to Group T (P=0.03731) (Fig. 1). There were no anaesthetic related complications in any of the patients. Complete akinesia of the eyeball was achieved in most of the patients receiving peribulbar block (86%) while some movement persisted in all of the patients receiving the topical–intracameral anaesthesia.

Discussion
Topical anaesthesia has recently become popular in the ophthalmic surgery. It has been successfully employed for phacoemulsification during cataract surgery. Unpreserved 4% lignocaine, unpreserved 1% ropivacaine, 0.5% tetracaine and 0.4% oxybuprocaine hydrochloride have been used topically for cataract surgery. Topical anaesthesia has also been successfully used for penetrating keratoplasty. Riddle et al. found that lpa receptor patients experienced mild discomfort when a penetrating keratoplasty was performed under topical anaesthesia only. It was further noted that discomfort arose when the lens was manipulated causing pain in the cilliary body and iris root areas. The combination of topical anaesthesia and intracameral injection of 1% lignocaine has been reported to produce acceptable levels of patient comfort. When intracameral injection was used in addition to topical anaesthesia, mean satisfaction levels of patients were found to be higher than retrobulbar anaesthesia. We found topical–intracameral anaesthesia to be adequate for the surgical repair of OGI, which concurs with the findings of Scott et al. and Boscia et al.

The O’Brien block is used to block the facial nerve at the proximal trunk. The condyloid process of the mandible is palpated just in front of the tragus of the ear by asking the patient to open and close his or her mouth. The process is felt to slip forward under the finger during this movement. At the site of injection, the skin is partially anaesthetized by raising an intradermal wheal with the local anaesthetic. A 5ml syringe with a 24 G needle 1inch in length is used. The needle should pass straight down to the periosteum; 2–3ml local anaesthetic solution is injected, and after withdrawing the needle, firm pressure and local massage are applied. Paralysis of the orbicularis usually occurs within 7min.
We chose O’Brien technique because it is easy to administer, produces reliable effect and causes minimal local oedema or haemorrhage compared to the other techniques of facial block. In our study the average patient comfort as well as surgeon comfort levels were satisfactory in both Groups. Alternately, Scott et al. used peribulbar block and the patients were comfortable, Boscia et al. used only topical anaesthesia for repairing OGI and all of the patients complained of mild to moderate pain and the operating surgeons complained of discomfort. In our study incorporation of an intracameral injection of lignocaine eliminated pain arising from uveal tissue manipulation, providing a greater patient comfort. Additionally by preventing eyelid squeezing, (by application of facial nerve block) surgeons comfort increased. While akinesia was achieved in most of the patients receiving peribulbar block, some ocular movement persisted in all patients receiving the topical–intracameral anaesthesia.